"The agreement of the results seems to show that light and magnetism are affections of the same substance, and that light is an electromagnetic disturbance propagated through the field according to electromagnetic laws."

§ Maxwell's Theory of the Electromagnetic Field:

According to Maxwell's equations, electromagnetic radiation ( EM ) is a self - propagating transverse wave with electric and magnetic components where the oscillating electric and magnetic field components induce their respective opposites and vice-versa. These electric and magnetic components oscillate at right angles to each other and propagate perpendicularly to the direction in which they indefinitely travel unless absorbed by intervening matter. That is, each kind of field - electric and magnetic - generates the other in order to propagate the entire composite structure moving forward through empty space at the finite speed of light, c. In order of increasing frequency, the types of electromagnetic waves include radio and television waves; microwaves; infrared radiation; visible light; ultraviolet light; x - rays; gamma rays; and finally, cosmic rays.